Method and system for distribution of stand-by electric power

ABSTRACT

A method and system for distribution of stand-by electric power via a network separate from the standard or ordinary electric power network is disclosed. Voltages are transformed/produced in voltage sources, TR and then branched off in control devices, S, to devices, A. The devices, A, distribute the voltages to loading equipment, for instance telecommunications devices, network equipment or medical equipment. Furthermore, surveillance devices, Ö, communicate with the voltage sources, the control devices, and the devices, A, to control electronic power drains, and to transfer control orders for execution.

TECHNICAL FIELD

The present invention relates to a method and a system for stand-byelectric power distributed via network separated from the ordinarynetwork for distribution of electric power.

TECHNICAL PROBLEM

There is a need to guarantee the electric power supply to importantsystems or devices during service interruptions whether they be short orlong interruptions. Known solutions utilize batteries or stand-byelectric power stations that are normally locally arranged at arespective system/plant. For, for instance, telecommunications operatorsthis implies that stand-by electric power is arranged at each plant. Forsubscriber telecommunication terminals, the subscriber has, in eachcase, to arrange for the necessary stand-by electric power. Maintenanceof batteries and/or standby electric power stations is burdensome bothfrom an economical and a resource point of view. In the future, stand-byelectric power, for telecommunication devices located at subscribers,will be required to guarantee the operation of the device at drop out ofthe ordinary electric power supply.

A general introduction of stand-by electric power is expensive anddifficult, and the use of batteries on a large scale may result inunwanted environmental stress.

Example 1: Society is becoming more and more dependent on the supply ofelectric power and telecommunications. This increased vulnerabilityincreases the importance of functioning telecommunications during dropouts of the ordinary electric power supply. Technical developments inthe telecommunications field has resulted in an increased dependence onpublic electric power supply. This dependence should be reduced in orderto satisfy the demands of the public on service and security.

Traditional telephone sets have electric power supply arranged via thetelecommunication network. These telephone sets are operating viacentral battery systems, and can be utilized as a “life-line” functionto call for aid in emergencies or in case of drop out of the publicelectric power supply. Telephony functions are utilized e.g., byelectric power companies, to restore the electric power supply.

Modern and future subscriber devices are consuming electric power tosuch an extent that the ordinary lines of the telecommunication networkcan not be utilized, but electric power supply from the public electricpower network is required. In order to avoid problems withtelecommunications during drop out of electric power supply, it isnecessary that the subscriber devices be equipped with stand-by electricpower. In future telecommunication networks, fibre-optic connectionswill be arranged right up to the telecommunications device. As a result,the “life-line” function of traditional telephone systems will notexist.

Example 2: Technical devices which require electric power supply areused in more and more places for important functions, which shouldoperate without interruption, in both homes and commercial and publicfacilities. Medical devices for care in the homes of seriously illpersons may may require stand-by electric power in order to guarantee acontinuous life-sustaining process. Computer equipment for informationservices often requires continuous operation. Electric power demandingprocesses in connection with keeping of animals may be vital for thestock of animals.

In order to bridge these problems, the telecommunication network can beequipped with devices which provide stand-by electric power at a highercapacity than can be currently transmitted in the telecommunicationnetwork for internal needs and to subscriber devices. The power that canbe supplied is small compared with the power capacities of the publicelectric networks. At electric power interruptions in the publicelectric networks, there consequently is a big need that stand-byelectric power is available at the telecommunication subscribers. Theelectric power supplies at that must be restricted and strictlyregulated. In order to avoid overloading, also control and powerlimiting systems must be introduced in order to utilize the stand-byelectric power supply system optimally, and to achieve operation withoutproblems at electric power interruptions in the ordinary electric powersupply network.

The present invention has the intention to solve above mentionedproblem.

PRIOR ART

It is previously known to provide systems and devices with stand-byelectric power from batteries or stand-by electric power stations.Operation of conventional telephone equipment has been arranged by theoutput voltage from the telephone lines. Increased security in electricpower supply also has been arranged by connection of a multiple ofelectric power distribution networks.

Device for surveillance and control of the electric power consumptionaccording to plan in system or equipment is known from e.g., U.S. Pat.No. 5,625,236.

THE SOLUTION

The present invention constitutes a method and a system for distributionof stand-by electric power characterized in the following patent claims.

The present invention relates to distribution of electric power which iscontrolled via a telecommunication network. Voltages aretransformed/produced in voltage sources, TR. These voltages are branchedoff in control devices, S, to devices, A, which distribute the voltagesto the subscribers' systems/equipment, for instance telecommunicationsequipment, computer equipment and the like. Surveillance devices, Ö,communicate with the voltage sources, the control devices, and therespective the devices, A, concerning measurement of the currentelectric power drain, and the transferring of control orders forexecution of changes in electric power drain, connection anddisconnection.

ADVANTAGES

The invention implies that electric power is distributed alternativeroutes in relation to ordinary electric power distribution. Further isoffered that an alternative distribution of electric power is obtainedin case of drop out of electric power from the electric power supplier.The provides, on one hand, to arrange a common electric power sourcewhich will function when ordinary electric power supply has dropped out,and on the other that, systems/equipment which require electric powerfrom the electric power network will also function when distribution ofelectric power from the ordinary electric power supplier has droppedout. The control system further makes possible control of drained power,such that the utilization of available power can be optimized withregard to actual need. The invention further provides that the stand-byelectric power system can be dimensioned optimally in relation toforeseen needs. In traditional electric power systems the system isdimensioned according to a maximal need to prevent overload. The presentinvention includes control functions which supervise the load in thedifferent parts of the stand-by electric power network, and disconnectparts which give rise to overload. Further, the load in the differentparts of the electric power network can be controlled at differentoccasions.

DESCRIPTION OF FIGURES

FIG. 1 shows block diagram of a system in accordance with an embodimentof the invention; and

FIG. 2 shows block diagram of a device A, in accordance with anembodiment of the invention.

PREFERRED EMBODIMENT

In the following, the invention is described on basis of the figures andthe indications in them.

A separate electric power network is provided by a supplier of stand-byelectric power, in addition to the standard power supply network, STN.Stand-by electric power network voltages are distributed via voltagesources, TR, for instance transformers, electric power stations and thelike. These voltage sources produce alternating or direct voltagesadapted to the characteristics of the distribution network. These firstvoltages are distributed out on the network. The produced electric poweris received in control devices, S, placed in points in the electricpower network where the voltages are branched off. The branched offvoltages consist of other voltages suited to be transferred in thebranched off networks. These control devices can in other embodiments beplaced close to, or in, devices, A, placed at subscribers. The controldevices include voltage converters which convert the transferred voltageto a third voltage, for instance 220 V that is appropriate for userdevices.

The control devices are equipped with communicative means and means forcontrol of drained electric power. The control devices further includefunctionalities for connection and disconnection of the electric powerdistributed to the devices, A. In order to determine the electric powerdrain, the control devices include units which define the allowed powerdrain for each device's respective equipment. The control devices, S,obtain information by permanent programming, or by external measures. Afirst external measure is that users connected to the devices, A, areallocated cards which are connected in the control device, S, and/or thedevices, A. These cards preferably are of type smart cards, i.e. cardsequipped with micro chips which have been programmed by supplier ofstand-by electric power. For validity and/or security measures anidentification of the control device/device and, if necessary, also anidentification for the subscriber and the allowed maximal drained powerare provided on the cards. The identification consists of numeric oralphanumeric information which clearly indicates each plant. Said cardis pushed into the control device in for this purpose intended place,for instance a slot into which the card is inserted, or a specialcardplace in the control device. In the latter case, the connection ispreferably made by personnel authorized by the supplier of the stand-byelectric power. In the first case, the user of the equipment buys orreceives the card over the counter. The user after that himself/herselfapplies the card to the equipment. Further alternatives are that changesin the control equipment are transferred to the control equipment byprogramming via the telecommunication network. In this case the operatorindicates the identification for the control device in question andactual plant. The control device responds to the call with agreedsignals, after which the programming changes can be introduced. Theprogramming can also be introduced in a central database which isutilized by the control system for programming of the control devices.

In the cases where the control system utilizes one or more databases,the control system controls time of the 24 hour period, days of theweek, existing holidays, time of the year etc. Depending on thesecriteria is after that decided, by utilizing suitable software, whichchanges in existing restrictions that shall be introduced. In this wayavailable electric power can be distributed according to an actual need,which also makes it possible for the supplier of stand-by electric powerto efficiently optimize his/her resources for distribution.

The invention provides, for instances that a plurality oftelecommunication stations and nodes in the telecommunication networkcan be allocated stand-by electric power over an alternative electricpower network in the cases where ordinary electric power distributionhas dropped out. To the telecommunications operator this means thatsurveillance of batteries and/or local stand-by electric power stationscan be minimized without the functionality of the telecommunicationnetwork being at hazard.

The devices, A, further include the ability to connect a plurality ofsubscriber devices, for instance telephones, data equipment etc, inorder to obtain electric power. Each connection is arranged to obtain anindividually defined power drain. Alternatively a maximal power drain isgiven for a defined system/plant, or for a subscriber of stand-byelectric power.

The control devices, S, further, are in their database giveninstructions regarding the control of the electric power system in caseof power drop out, which affects the electric power distribution in theelectric power network. In such cases, the plants are prioritizedaccording to the public welfare, or other relevant criteria.

According to the invention a first voltage is converted in voltagesources, TR. These voltage sources consist of transformers which obtaintheir driving voltage from an ordinary electric power network. Thesevoltage sources, TR, further are equipped with stand-by electric powerfeeding, which is connected in case of drop out of the electric powersupply from supplier/suppliers of electric power. The stand-by electricpower is produced in customary way by generators driven by dieselengines or other suitable device. Alternatively, or as complement,batteries are utilized which via inverters produce the necessaryelectric power until its stand-by electric power supply is in operation.In connection to the voltage sources, TR, there are sensing units whichmeasure phase, frequency and voltage, which information is transmittedto surveillance devices, Ö, via, for example, the telecommunicationnetwork. The surveillance devices find out whether the measuredparameters are in accordance with decided criteria. If deviations arefound, orders for corrections are returned. The surveillance device, Ö,further compares the electric power supply from different voltagesources, and orders them individually for adjustments for supply of apromised electric power quality. In the described, the starting point isthat alternating voltage shall be supplied from the voltage sources, TR,but the procedure also can be applied at distribution of direct voltagewith necessary modifications. The from the voltage sources suppliedvoltages are adapted to a current need, for instance “household voltage”at direct supply to subscriber, or other voltage which is transformed tosuitable distribution voltage.

The produced voltage after that is transferred in the electric powernetwork to control devices, S, where the electric power is transferredto the devices, A. The control devices, S, include correspondingcommunicative means and the voltage sources, TR, for communication withthe surveillance device, Ö. The surveillance device, Ö, receivesinformation from the control device regarding drained electric power andreturns control order, which may relate to switchings in the network,such as disconnection of a load if power drain is too high.

Each of the devices, A, is equipped with one or more outlets where oneor more devices, for example, telephones, data-equipment, telephoneexchanges, medical equipment and the like are connected. Each outlet canbe defined for individual electric power drain. The surveillance of thepower drain in each of the outlets is made in corresponding way as hasbeen described above. In order to reduce the risk of too high powerdrain, due to communication problems, each device is equipped with localsurveillance. The parameters for this surveillance is transferred in afirst case from the surveillance device, Ö, to the local memory of thedevice and surveillance system. In the case that too high a power drainis observed in the control system of the device, disconnection isexecuted in the same way as has previously been described. Informationregarding allowed electric power drain is further programmable viaseparate terminal or by means of, for instance, a smart card.

By the utilization of programmed surveillance, power drain is madepossible which varies in time, for instance depending on time in thetwenty-four hours, day of the week, holidays, season etc. Theconstruction of the stand-by electric power network in this way can beadapted to the need to utilize the stand-by electric power networkoptimally and avoid fatal overloads.

Telephones, data equipment, telephone exchanges, nodes in thetelecommunication network, medical equipment and/or other devices atsubscribers of stand-by electric power can be connected with a stand-byelectric power network which is laid together with the telecommunicationnetwork. The electric power network at this need not necessary be laidparallel with the telecommunication network, but other arrangements oflaying are possible. Stand-by electric power is generated by forinstance diesel engines arranged at, or at least in connection with, atleast some telephone exchanges. At the same places are further connectedpublic electric power supply. The electric power from the publicelectric power network, or the stand-by electric power, is distributedin the stand-by electric power network to subscribers of stand-byelectric power. In the network terminals are further arranged outletsfor electric power supply to the subscribers' systems/devices.

The invention relates to distribution of stand-by electric power. Thevoltage is produced/transformed in, for instance, diesel generators ortransformers. The distribution to subscribers of stand-by electric powercan be made on different voltage levels and transformed in one or moresteps to suitable voltage for the subscriber's need, and be supplied forinstance as “household voltage”, one or three phase. Centrally thesupplier of stand-by electric power has a control computer withdatabase. The subscriber is allowed a maximal power which must not beexceeded. In the nodes of the stand-by electric power network, thevoltages are transformed and branched off. There also are surveillanceand control devices, which are permanently programmed, or can beprogrammed from the control system. They are independently executing, orcan be ordered from the control-system. If the power drain exceedssubscribed power, the control devices are activated and disconnect thesubscriber. In the measuring unit of the control unit there may be basicdata for debiting of consumption of stand-by electric power. The controlsystem will, via the telecommunication network, have information aboutcurrent load situation and can, on basis of information in the database,decide which subscribers that exceed their allowed power. The controlsystem orders the control devices to disconnect these subscribers andprevents that the stand-by electric power system is overloaded and hasto make an emergency stop, with functional trouble as a consequence. Thecontrol system puts together data for debiting.

The invention is not restricted to the above described example ofembodiment or to following patent claims, but may be subject tomodifications within the frame of the idea of the invention.

What is claimed is:
 1. System for distribution of stand-by electricpower, characterized in that the system includes stand-by electric powerproduction in stand-by electric power stations or transformers (TS)distributing electric power to devices (A) over a separate electricpower network, which is separated from the electric power supplierselectric power network, that maximal values for the electric power drainof said devices are decided in control devices (S), that load isswitched on basis of drained electric power, available electric powerand stored or added criteria, and that the control devices obtaininformation regarding allowed drained electric power at each of saidelectric power drains, the electric power drain of which is arranged tobe depending on the time of the twenty-four hours, day of the week, andseason.
 2. System according to patent claim 1, characterized in thatsaid control devices are located in immediate connection to said devicesand/or at branch points for the electric power distribution to saiddevices, and that said control devices include voltage convertingdevices, and that to each of said control devices one or more of saiddevices are connected, and that the control devices are arranged tosupervise each electric power drain of said devices separately. 3.System according to patent claim 1, characterized in that the controldevices obtain information regarding allowed drained electric power ateach of said electric power drains, the electric power drain of which isarranged to be depending on the time of the twenty-four hours, day ofthe week, and season.
 4. System according to claim 1, characterized inthat information is transmitted from centrally located control systemincluded in the system to said control devices regarding allowedelectric power that can be drained, that information regarding allowedelectric power that can be drained is stored in said centrally locatedcontrol system, and that allowed electric power that can be drained canbe stored locally in said control device.
 5. System according to claim 1characterized in that a centrally located control system obtainsinformation regarding allowed electric power drain for said devices viacentral programmings, that said information is transferred to saidcontrol devices via a telecommunications network, and that the locallylocated storing devices obtain information regarding allowed electricpower drain via special information transmitters, and that during dropout of communication between said control devices and said centrallylocated control systems, the information which has been stored in thelocal storing devices applies.
 6. System according to claim 1,characterized in that each of said devices is allocated a uniqueidentification, that the identification is transmitted in atelecommunication network from said control devices to a centrallylocated control system, that information regarding drained electricpower is transmitted to said centrally located control system togetherwith the identification, and that the transmissions in thetelecommunication network are digital.
 7. System according to claim 1,characterized in that surveillance devices (Ö) included in the systemstore information regarding said devices, that said surveillance devicesoptimize the utilization of the stand-by electric power system byallocating said devices the electric power which is predetermined,respective the electric power which can be allowed with regard to acurrent situation, and that said surveillance device synchronizes tothe, to the stand-by electric power system connected, voltagetransformers, such as stand-by electric power stations, transformers andinverters.
 8. System for distribution of stand-by electric power,characterized in that the system includes stand-by electric powerproduction in standby electric power stations or transformers (TS)distributing electric power to devices (A) over a separate electricpower network, which is separated from the electric power supplierselectric power network, that maximal values for the electric power drainof said devices are decided in control devices (S), that load isswitched on basis of drained electric power, available electric powerand stored or added criteria, and that a first voltage is produced atsaid stand-by electric power production, that said first voltage isconverted to at least a second voltage in said control device, that saidsecond voltage is distributed to said devices, which convert said secondvoltage to a third voltage, for instance a household voltage.
 9. Systemaccording to claim 1, characterized in that the stand-by electric powerconsumption is registered in the devices (A), that the informationregarding the stand-by electric power consumption is transmitted to thesurveillance devices (Ö) and stored in the database, and that theinformation data for the debiting is put together in said centrallylocated control system regarding the stand-by electric powerconsumption.